Question about MIN/MAX optimization

Hi all,

Db2 v8 FP15 LUW .

create table T (ID varchar (24), ABC timestamp)

There is an index for (ID, ABC), allowing reverse Scans.

My application needs to determine MIN and MAX(ABC) for a given ID. We
are currently using a simple statement:

select MIN(abc), MAX(abc) from T where ID = ? for read only

Table T has 100+ million rows, and several other applications are
reading/deleting data from it. The statement above runs with UR
isolation, however it takes a very long time to complete (5-10
minutes, or more).

I have studied the access plan, and it looks OK:

Access Plan:
-----------

        Total Cost:             25.6855
        Query Degree:           1

              Rows
             RETURN
             (   1)
              Cost
               I/O
               |
                1
             NLJOIN
             (   2)
             25.6855
             3.99557
          /-----+-----\
        1                1
     GRPBY            GRPBY
     (   3)           (   5)
     12.8262          12.8587
     1.99557             2
       |                |
     46.1442          46.1442
     IXSCAN           IXSCAN
     (   4)           (   6)
     12.8544          12.8544
        2                2
       |                |
     973678           973678
 INDEX: RTM       INDEX: RTM
   IPSSTAT_WIN      IPSSTAT_WIN


I am looking for some magic SQL or hint that will allow me to improve
this rather 'simple' query.

PS: Yes, table and indexes do have updated statistics.

Thanks in advance,

-Michel